thomas asceoft walker



(No Model.)

J. S., T. A. 8a E. R. WALKER.

AIR VALVE.

Patented Deo. 7, 1886.

mumnuin t IIIIIIIII N. Pneus, Phmwmngnphur ash... wn n UNITED STATES PATENT OFFICE.

JOHN SOARISBRIOK VALKER, THOMAS ASOROFT VALKER, AND EDVIN ROBERT VALKER, OF VIGAN, COUNTY OF LANCASTER, ENGLAND.

SPECIFICATION forming part of Letters Patent No. 353,995, dated December 7, 1886.

Application tiled November :'10, 1885. Renewed November G, 1886. Serial No. 218,216. (No model.) Patented in England October 17, 1884, No. 111,730, and in Belgium July 16, 18:5, No. 69,607.

To all lull/0772, it may concern:

Be it known that we, JOHN SoiRIsRRroK WALKER, Tetonas AsoRoF'r WALKER, and EDWIN ROBERT WALKER, subjects ot' the Queen of Great Britain, residing at \Vigan, in the county of Lancaster, in the Kingdom of England, have invented certain new and useful Improvements in Air-Valves, (for which application was made in Great Britain dated ro October 17, 1884, No. 13,730, and which was sealed on October 13, 1885, and in Belgium, dated July 16, 1885, No. 69,607,) of which the following` is a specification.

The object of this invention is to prevent the dancing, to regulate the opening and general controlling ofthe air-valves, and thus enable the latter to last much longer than at present, and further enable the engines to work at a greater speed without injury than 2o is practicable with valves not controlled in this manner.

Referring to the drawings, Figure 1 is a top plan view, partly in section, of our improved valve; Fig. 2, a longitudinal section of the same, and Fig. 3 a vertical cross-section through the valve-controlling spindle.

.A is the valve of ordinary type.

B is a link pivoted to valve at b, and to steadying-block O at b.

G is a steadying-bloclr in cylinder D, open above and below to the pressure of the coinpressed air.

D is a cylinder forming part of the valvechaniber cover and iitted with cover and stuffing-box.

F is a hollow spindle connected xedly with steadying block and open to the pressure of the compressed air.

G is a stationary cylinder on end of hollow 4o spindle open to the compressed air through the hollow spindle F. Itwill be seen that the inner end of block C has its entire area or cross-section exposed to the air-pressure, whereas the pressure upon its outer end is reduced by the presence of spindle F to just the extent of the cross-section or area of said spindle. It is for this reason that the spindle is made hollow and the closed stationary cylinder G provided, the air passing through the 5o spindle F to cylinder G, and pressing inward set-screw k.

upon the end of the spindle, thereby compensating for theloss just mentioned and perfectly balancing the pressure. The end F of spindie Fwliere it enters G is made preferably rather larger than where it passes through cylinderl D, so that there may be a little additional pressure tending to keep the valve closed. For this purpose the enlargement takes place atjoint f. The hollow spindle F is jointed at f with a'screw-socket joint for convenience of construction, and in order to get the spindle through the parts hereinafter described.

H-is the valvechest, I cover of same formed in one with the cylinder D.

. d is an oil-hole on the upper side of the apparatus, when, as is usually the case, this controlling mechanism is arranged horizontally, as shown. The oil holes in the block andlink can be oiled through this.

d is the cover of cylinder D.

J is a battering-plate having lock-nutj. and each having an internal screw ttin'g the spindie F, screwed at this point. By this means the buffering-plate J can be adjusted longitudinally and heldin position by the locknut j.

K is a pedestal to support buffer.

The

thread can be turned off. as shown, from the spindle F at those parts inclosed by this pedestal.

la is asleeve or quill held in the pedestal by This sleeve is roughened on its surface with teeth or ridges pointing toward the center of the pedestal. so as to hold the rubber blocks L L firmly in place. Y

L L are buffers, of rubber or other elastic material, xed into the ring hollow-iormed between pedestal K and sleeve la.

M is a second buffer-plate screwed onto spindle and provided with lock-nut m.

N is a third bufferplate, also screwed onto shaft and provided with lock-nut n.

P is a spring pressing against nut or buffer plate N at one end and cross-piece Q at the other.

Q is a crosspiece carrying and preferably formed in one with cylinder G. This and cross-piece K are supported by pillar bolts R R. These bolts pass through and are firmly ioo fixed to lugs in cross-piece K,cylinder D, and

cylinder-cover d by collars r r`' and nuts fr r4. They are also firmly secured to cross-piece Q by shoulder ri and nut ri.

The cylinders G and D are supplied with stuffing-boxes, as shown.

The mode of action is as follows: The Valve, opening under the pressure in the blowing` engine cylinder, pushes back spindle F, compressing spring P, and bringing the bufferingplate J against buffers L. The shock has, however, been chiefly taken up by the spring P. The valve closing would do so with strong impact, but that before the actual impact of the valve upon its seat buffering-plate M strikes elastic buffers L', and thus cushions the blow. It will thus be seen that as the valve begins to open it has opposed to it only the spring at least tension. As it opens wider the strength of the spring increases and the valve comes to rest with the quickly-applied and rapidly-increasing buffering action between J and L. In closing the spindle has the full force of the spring tending to close it; but this decreases as thevalve nears its seat. It has the constant resistance of the friction of the parts, and, lastly, as the valve gets in immediate vicinity of the seat the buffering takes place. The nut J being adjustable, the amount-of opening of the valve can be regulated. The area of crosssection of the spindle F, projecting through cylinder D, being less than the area of pressure in cylinder G and the end of the spindle, there is a slight excess of pressure, always tending to close or keep closed the valve. The various buffering-plates being attached to the spindle by screwing can be exactly regulated, being turned round on their axis more or less in either direction, as required, and clamped by their check-nuts.

We claim as our invention- 1.' The combination of the spindle F, having thread cut thereon, with bufenplates J and. M, and corresponding lock nuts screwed thereon on each side of buffering devioeL L',

whereby the exact amount of buffering on either side can be regulated by screwing the buffer-plates round and then locking them with the nuts, substantially as described.

2. In a valvebu'ering apparatus, the coin- 5o bination of a hollow valve-controlling spindle,

F, projecting from the valve-chest through a stuffing-box with a terminal cylinder, G, hav ing connection with the valve-chest, and thus balancing the otherwise unbalanced pressure caused through the area on one side the Valve, and its connectionsexposed to the fluid in the valve-chest being less by the sectional area of the spindle than on the other.

3. The. combination of the Avalve-chest, the 6o hollow valve-controlling spindle F, passing the air under pressure, and the terminal cylinder G,open to the pressure inthe valvechest through spindle F.

4. The combination of the valve-chest, holf low Valve controlling spindle F, joint f, with a spindle of enlarged diameter beyond, and cylinder G, inclosing enlarged spindle7 `open to the pressure in the valve-chest, whereby there is a slight unbalanced pressure tending7o to keep the Valve closed.

5. In combination with an air-chamber, a valve, a cylinder communicating with the chamber, a hollow block or piston connected with the valve, working in the cylinder, and havinga hollow stem secured to it,and a closed stationary cylinder at the outer end of the hollow stem, communicating with the air-chamber through the hollow stem. j

In testimony whereof we have signed our 8o names to this specification in the presence of two subscribing witnesses.

JOHN SCARISBRIOK WALKER. THOMAS ASOROFT WALKER. EDWIN ROBERT WALKER.

.Witnessesz J oHN THoMrsoN BREwsrEn, JOHN BUXroN.

WM. PITMAN, ll Queen Victoria Sfreet, London, Solicitor for Commissioner to Administer Oaths 'in the Supreme Court of Indenture.

W. WV. MARTIN, Clerk to Messrs. Pitman t Sons, 11 Queen Vie toria Street, London, Solicitors. 

